Submitted to: In Vitro Cellular and Developmental Biology - Plants
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/29/2012
Publication Date: 9/12/2012
Citation: Cheniany, M., Ebrahimzadeh, H., Vahdati, K., Preece, J.E., Masoudinejad, A., Mirmasoumi, M. 2012. Content of different groups of phenolic compounds in microshoots of Juglans regia cultivars and studies on antioxidant activity. In Vitro Cellular and Developmental Biology - Plants. 1-8. Interpretive Summary: Walnut shoots growing in tissue culture were analyzed for their growth, phenolic compounds, and antioxidant activity. The tissue culture shoots contained phenolic compounds with antioxidant activity, similar to shoots on trees. The relationship between shoot growth, phenolics and antioxidant activity merit further study. This is the first report on these compounds in walnut shoots grown in tissue culture.
Technical Abstract: Phenolic and other compounds were extracted from micropropagated axillary shoots (microshoots) of the walnut (Juglans regia L.) cultivars ‘Chandler’, ‘Howard’, ‘Kerman’, ‘Sunland’, and ‘Z63’. Among cultivars, microshoots showed differences in phenolic compounds, phenolic acids, flavonoids and proanthocyanidin. All cultivars contained the phenolics acids chlorogenic acid, gallic acid, and p-coumaric acid; the naphthoquinone juglone; and the flavonoid quercetin. Flavone was not detected in any cultivars and the phenolics acids syringic acid and vanillin were present only in microshoots of ‘Howard’. Microshoot extracts had different antioxidant activity with ‘Kerman’ the highest and ‘Chandler’ the lowest in each of three antioxidant assays: the phosphomolybdenum assay (PPM), reducing power assay, and 2,2-diphenyl-1-picrylhydrazyl (DPPH)-scavenging effect. There was a strong linear relationship between total phenolic compound content of microshoots and increasing antioxidant activity.